Drill bit



A. P. HUMMEL DRILU BIT Filed March 4, 1935 A TTORNEY Patented oci. 1s,193s UNITED STATES PATENT OFFICE The invention relates to well drillingtools and" more especially to a drilling bit of the type wherein acontinuous stream of water is injected into the hole being drilled.

The lprimary object of the invention is the provision of a bit of thischaracter, wherein the flow hole for the water has therein aresilientbushing to reduce materially the friction created by passage of thewater and slush under pressure through the hole in the body of the bitand thus to increase the longevity and consequent usefulness of thetool.

' Another object of the invention is the provision of a bit of thischaracter, wherein the same has the water passages therein lined with awear resisting material. of elastic kind, such as rubber, which throughits use` pressure fromthe pump will remove any accumulationof materialwhich may become wedged in the passage and also functions to. hold thelining material rmly -in applied position in the passage in the bit.

A further object of the invention isthe provision of a bit of thischaracter, wherein the lining is interchangeable and 'replaceable whenthe same becomes worn by the contact of sand and other cuttingsubstances passing at high velocity through the iow hole therefor andunder pump pressure. A still further obiect'of the invention is theprovision of a bit of this character, which is simple in construction,thoroughly reliable and efIlcient in its operation, strong, durable. andinexpensive to manufacture.

With these and other objects in view, the invention consists in thefeatures of construction,

combination and arrangement of parts as will be hereinafter more fullydescribed, illustrated in the accompanying drawing, which discloses thepreferred embodiment of the invention and pointed out in the clain`hereunto appended.

In theI accompanying drawing:

Figure 1 is a fragmentary vertical sectional view through a drill bitconstructed in accordance with the invention.

Figure 2 is an enlarged sectional view throughthe lining for the ow holein the bit.

Figure 3 is a perspective view of the bushing sponding parts throughoutthe several views in the drawing.

Referring to the drawing in detail, particularly Figures 1 to 3,inclusive, there is shown in Figure 1 an improvedV type of-bit, the bodyI0 being 5 formed with a shoulder I I set at an angle rto allow forrapid circulation of water and to direct the same upward past the shankI2 without interference thereby to retard its progress. The bit isfurther provided with a cutting blade I3 so dis- 10 posed as to insuremaximum cutting eciency.

It is to be understood, however, that the co'nstruct-ion of the bitshown and specically described does not in any way restrict the useofthe invention to be presently referred to. as the in 15 vention isadapted for applicationto. any type of earth boring tool employing thecirculation of fluid as a. lubricating medium.

The shank has provided therein' a cavity I4 from which'leads a hole orwater course I5 which 20 is trained downwardly and outwardly from thebottom of this cavity to a proper point for 4discharging uid on theoperative surface of the blade I3. When the water course I5 becomesplugged by accumulation of substances therein it is obviously necessaryto withdraw`the blt from the hole being bored .with the addeddisadvantage of having to lift the column of water entrapped in thedrillstem assembly and requiring that such water be released. To reducethe likelihood of plugging'the water course I5 in the bit the presentinvention has been created and comprises a copper coated steel sleeve I6 of a cross sectional diameter corresponding to that ofthe water courseI5 for snug fitting theref in and this sleeve is preferablylongitudinallyl slitted at I'I which slits extend through one end andterminate short of the other end which carries an outturned rim or nangeI8. The rim or flange I8 in its entirety is embedded in a rubber liningI9 which extends inside of the sleeve I6 for the full length thereof andthe same is vulcanized therewith. This lining of elastic material avoidsthe wearing away of the water course I5 when the sleeve is iittedtherein.

The rim orange end I8 of the sleeve constitutes an abutment against thewall of the cavity It so as to avoid the working of the sleeve Itthrough the course I5 when the iluid ilows through the latter, underhigh pressure and the 50v slitting of the sleeve I6 permits theexpanding of the sleeve by the high pressure exerted against the same sothat the sleeve. will firmly bind in the course I5 and be held in place.

In Figure 3- of the drawing there is showna 55 Um the sleeve :scarrying, the elastic lining :c

has the anged end 21 overlapped by a. rim 2l on the lining 26. i

A The bushing could be constructed without the use of the copper coveredsteel sleeve around which the rubber is iltted as it is contemplated forthe useof steel spring mesh wire, either brass or copper covered as abushing.

What is claimed is: l

In a drill bit. having a. water ow hole therel through, an elastictubular bushing fitting said hole and including a metallic sleeveremoved from the wall of the bore of said bushing.

ARTHUR P. HUMMEL.

